Efficient remote data access in a mobile computing environment

Considers the problem of remote data access for multiple clients in mobile computing environments. In this environment, a base station provides a wireless communication link between the mobile clients and remote servers that reside on a fixed network. Clients send requests to the base station for objects which reside on the remote servers. The base station downloads these objects from the remote servers and transmits them to the clients. A drawback in this environment is that remote data access across a fixed network is slow. When locally cached copies of data exist at the base station, accessing them reduces latency. However, the cached data becomes old as more recent data is made available at the remote servers. In this paper, we consider a framework that allows mobile clients to specify their preferences about recency. The objective is to maximize the recency of the data for all clients while delivering data to the clients as quickly as possible. We develop an on-demand strategy which determines when the base station should access data from the remote servers and when it should return data copies from its cache. We present analytical results that show the benefits of the on-demand approach